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Here's the forecast for the incoming weather system from the National Weather Service for our area:

KEY INFORMATION:
A fairly strong weather system will be moving through Northern California beginning today (Tuesday). The initial brunt of the storm is still expected to impact the area late today and Wednesday... but the snowfall in particular is now also expected to linger into late Thursday and possibly early Friday. Most significant will be the high amounts of snowfall in the mountains and the chance for snow accumulations well down into the foothills. The strongest period of the storm is expected between late Tuesday night and late Wednesday night. Periods of rain in the valley and snow in the foothills will continue into Thursday while snow will continue to fall in the higher elevations of the Sierra Nevada potentially into early Friday.

SYNOPSIS:
The storm will begin with windy conditions developing on Tuesday then precipitation moving into the area by Tuesday afternoon, moving from north to south. The winds will lessen by late morning Wednesday and the sustained precipitation will lessen by overnight into Thursday. However, periods of rain will continue on Thursday. Most locations in the Central Valley will have winds 15-30 mph sustained with gusts to 40 mph and will receive between 0.25 and 0.50 inches of rain. Some locations will have sustained winds to 35 mph with gusts to 45 mph and precipitation up to an inch.

In the mountains, winds are expected to be 25-45 mph sustained with gusts along the ridges up to 75 mph. Snow accumulations will be four feet or more at the highest elevations, with up to three feet at the trans-Sierra pass levels and a foot or more at the 5000 foot level. Snowfall rates in these areas will be 2-4 inches per hour at times. Four to eight inches of snow is expected between 2000 and 5000 feet with lesser amounts down to 1500 feet and flurries possible down to 1000 feet.

These conditions will begin by late Tuesday in the Northern Mountains and by Wednesday morning in the Coastal and Northern Sierra Nevada Mountains. Precipitation will be sustained through Thursday morning then begin to be more showery by late on Thursday. Snowfall will linger in the higher elevations of the Sierra Nevada Mountains into early Friday morning.

The heaviest snowfall in the foothills will come on Wednesday. By early on Thursday, the foothills will have periods of snow with some areas getting very little additional accumulation and others having brief periods of heavier accumulation.

IMPACTS:
Heavy snowfall will make most local and county roads hard to keep clear and even interstates and other major highways will have periods of time when the visibilities will be very poor due to the heavy snowfall rate. In addition... road conditions in the foothills will vary considerably and this will make travel especially hazardous. Some roads may be dry in some sections and slick with snow accumulation in others. The heavy snow could cause damage to power lines and rooftops especially if wind gusts are strong in the area.

Major waterways will be able to handle the precipitation. Small creeks and streams may rise quickly but should stay in their banks unless a lot of debris has collected and not been cleared.

FORECAST CONFIDENCE:
High confidence in the wind forecasts as well as the rainfall and liquid equivalent of the snowfall. Moderate to high confidence in the total snowfall amounts. Low to moderate confidence in the amount of snow that will fall in the foothills. The current forecast has four inches falling near 2000 feet but this amount may fall a little lower or a lot higher if the colder airmass doesn't move in as quickly as expected. We currently (130pm Tuesday) have a Winter Storm Warning out for the foothills. This will likely stay in place until Thursday when it may be downgraded to a Winter Weather Advisory due to the more showery nature of the snowfall.

The Sheriff's Office of Emergency Services would like to remind travelers to take precautionary/preparedness actions. Conditions can deteriorate rapidly during winter storms so please slow down and allow extra time when travelling. Carry tire chains, food, water, blankets and a flashlight in your car in case of emergency. Weather updates can be found on the National Weather Service website: www.nws.noaa.gov .

As always, please report any emergency situations via 9-1-1, and do not attempt to drive over, near, or around any downed utility wires. To report lane blockages, or other county road issues, please call 209-754-6402. To obtain the current status of snow removal on county roads, please call 209-754-6017.